问题
CheckSelfPermission method is not working as expected and it is always returning zero in android 6.0(Marshmallow). Because the target sdk is 22 and i am using http Client for network connection. Following is the code snippet.
private void insertDummyContactWrapper() {
List<String> permissionsNeeded = new ArrayList<String>();
final List<String> permissionsList = new ArrayList<String>();
if (!addPermission(permissionsList, Manifest.permission.ACCESS_FINE_LOCATION))
permissionsNeeded.add("GPS");
if (!addPermission(permissionsList, Manifest.permission.READ_CONTACTS))
permissionsNeeded.add("Read Contacts");
if (!addPermission(permissionsList, Manifest.permission.WRITE_CONTACTS))
permissionsNeeded.add("Write Contacts");
if (permissionsList.size() > 0) {
if (permissionsNeeded.size() > 0) {
// Need Rationale
String message = "You need to grant access to " + permissionsNeeded.get(0);
for (int i = 1; i < permissionsNeeded.size(); i++)
message = message + ", " + permissionsNeeded.get(i);
showMessageOKCancel(message,
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
requestPermissions(permissionsList.toArray(new String[permissionsList.size()]),
REQUEST_CODE_ASK_MULTIPLE_PERMISSIONS);
}
});
return;
}
requestPermissions(permissionsList.toArray(new String[permissionsList.size()]),
REQUEST_CODE_ASK_MULTIPLE_PERMISSIONS);
return;
}
insertDummyContact();
}
@TargetApi(Build.VERSION_CODES.M)
private boolean addPermission(List<String> permissionsList, String permission) {
if (checkSelfPermission(permission) != PackageManager.PERMISSION_GRANTED) {
permissionsList.add(permission);
// Check for Rationale Option
if (!shouldShowRequestPermissionRationale(permission)) return false;
}
return true;
}
private void showMessageOKCancel(String message, DialogInterface.OnClickListener okListener) {
new AlertDialog.Builder(MainActivity.this)
.setMessage(message)
.setPositiveButton("OK", okListener)
.setNegativeButton("Cancel", null)
.create()
.show();
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
switch (requestCode) {
case REQUEST_CODE_ASK_MULTIPLE_PERMISSIONS: {
Map<String, Integer> perms = new HashMap<String, Integer>();
// Initial
perms.put(Manifest.permission.ACCESS_FINE_LOCATION, PackageManager.PERMISSION_GRANTED);
perms.put(Manifest.permission.READ_CONTACTS, PackageManager.PERMISSION_GRANTED);
perms.put(Manifest.permission.WRITE_CONTACTS, PackageManager.PERMISSION_GRANTED);
// Fill with results
for (int i = 0; i < permissions.length; i++)
perms.put(permissions[i], grantResults[i]);
// Check for ACCESS_FINE_LOCATION
if (perms.get(Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED && perms.get(Manifest.permission.READ_CONTACTS) == PackageManager.PERMISSION_GRANTED && perms.get(Manifest.permission.WRITE_CONTACTS) == PackageManager.PERMISSION_GRANTED) {
// All Permissions Granted
insertDummyContact();
} else {
// Permission Denied
Toast.makeText(MainActivity.this, "Some Permission is Denied", Toast.LENGTH_SHORT)
.show();
}
}
break;
default:
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
}"
回答1:
The method Context#checkSelfPermission(String) was added to the API 23. Also below API 23 it's pointless as the permission is always granted. Make a check for the API version before handling the permissions
private void insertDummyContactWrapper() {
// the only way we insert the dummy contact if if we are below M.
// Else we continue on and prompt the user for permissions
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
insertDummyContact();
return;
}
List<String> permissionsNeeded = new ArrayList<String>();
final List<String> permissionsList = new ArrayList<String>();
if (!addPermission(permissionsList, Manifest.permission.ACCESS_FINE_LOCATION))
permissionsNeeded.add("GPS");
if (!addPermission(permissionsList, Manifest.permission.READ_CONTACTS))
permissionsNeeded.add("Read Contacts");
if (!addPermission(permissionsList, Manifest.permission.WRITE_CONTACTS))
permissionsNeeded.add("Write Contacts");
if (permissionsList.size() > 0) {
if (permissionsNeeded.size() > 0) {
// Need Rationale
String message = "You need to grant access to " + permissionsNeeded.get(0);
for (int i = 1; i < permissionsNeeded.size(); i++)
message = message + ", " + permissionsNeeded.get(i);
showMessageOKCancel(message,
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
requestPermissions(permissionsList.toArray(new String[permissionsList.size()]),
REQUEST_CODE_ASK_MULTIPLE_PERMISSIONS);
}
});
return;
}
requestPermissions(permissionsList.toArray(new String[permissionsList.size()]),
REQUEST_CODE_ASK_MULTIPLE_PERMISSIONS);
}
}
Reference: http://developer.android.com/reference/android/content/Context.html#checkSelfPermission(java.lang.String)
回答2:
If your application is targeting an API level before 23 (Android M) then both: ContextCompat#checkSelfPermission and Context#checkSelfPermission doesn't work and always returns 0 (PERMISSION_GRANTED). Even if you run the application on Android 6.0 (API 23).
It's not fully true that if you targeting an API level before 23 then you don't have to take care of permissions. If you targeting an API level before 23 then:
- Android < 6.0: Everything will be ok.
- Android 6.0: Application's run-time permissions will be granted by default (compatibility mode applies), but the user can change run-time permissions in Android Settings, then you may have a problem.
As I said in the 1st point, if you targeting an API level before 23 on Android 6.0 then ContextCompat#checkSelfPermission and Context#checkSelfPermission doesn't work. Fortunately you can use PermissionChecker#checkSelfPermission to check run-time permissions.
Example code:
public boolean selfPermissionGranted(String permission) {
// For Android < Android M, self permissions are always granted.
boolean result = true;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (targetSdkVersion >= Build.VERSION_CODES.M) {
// targetSdkVersion >= Android M, we can
// use Context#checkSelfPermission
result = context.checkSelfPermission(permission)
== PackageManager.PERMISSION_GRANTED;
} else {
// targetSdkVersion < Android M, we have to use PermissionChecker
result = PermissionChecker.checkSelfPermission(context, permission)
== PermissionChecker.PERMISSION_GRANTED;
}
}
return result;
}
In order to obtain target Sdk Version you can use:
try {
final PackageInfo info = context.getPackageManager().getPackageInfo(
context.getPackageName(), 0);
targetSdkVersion = info.applicationInfo.targetSdkVersion;
} catch (PackageManager.NameNotFoundException e) {
e.printStackTrace();
}
It works on Nexus 5 with Android M.
回答3:
When targeting an API level before 23, a compatibility mode applies. The old permission behavior is running, even on devices running Android 6. To use the new permission system, you have to target API 23 (or higher in the future).
The full behavior is specified on the documentation: https://developer.android.com/training/permissions/requesting.html
来源：https://stackoverflow.com/questions/33407250/checkselfpermission-method-is-not-working-in-targetsdkversion-22